Nowadays, various recording media for recording movies, music, data for PC, or the like are developed and commercialized. The flow of the development and commercialization starts from a CD-ROM (Compact Disc-Read Only Memory), a CD-R (Compact Disc-Recordable), or the like with a recording capacity of about 650 MB, and then is followed by a DVD-ROM, a DVD-R/RW, or the like with a recording capacity of about 4.7 GB, and further followed by a dual-layer type DVD-ROM, DVD-R, or the like with a recording capacity of about 8.5 GB. Lately, as the next generation disc of the DVD, a Blu-ray Disc with a recording capacity of about 27 GB has been developed. That is, the development and commercialization of such recording media have been promoted by each manufacturer, substantially from one viewpoint of an increase in the recording capacity.
Incidentally, there is no document having the content that is directly related to the construction of the present invention discussed below at the filing time point of the present invention.